The present invention relates to vibration isolation mounts and more particularly to an active pneumatic mount which can be energized by a controller to reduce, over a preselected band of frequencies, the vibratory force transmitted through the mount, while the mount supports a static load.
As is understood, there is increasing interest in controlling or reducing noise and vibration by active means, i.e., feedback controllers which energize a transducer so as to generate a cancelling noise or vibration. Such controllers typically utilize adaptive filters which are implemented digitally. The practicality and cost effectiveness of such controllers has been advanced by the availability of digital signal processors whose capabilities have advanced in correspondence with the advances in microelectronics generally.
While various active vibration isolation mounts have been proposed in the prior art e.g., U.S. Pat. Nos. 3,606,233, 4,600,863, and 5,052,510, such mounts have not been widely adopted due to their high cost and cumbersome nature. By and large, the problems confronted are associated with the sensing and driving transducers which are necessary to implement a practical active vibration or noise control system.
Among the several objects of the present invention may be noted that the provision of a novel pneumatic vibration isolation mount; the provision of such a mount which is active and can be energized to effectively reduce the vibratory force transmitted through the mount over a pre-selectable band of frequencies; the provision of such a mount which will support a substantial static load; the provision of such a mount which is easily fabricated; the provision of such a mount which is highly reliable and which is of relatively simple and inexpensive construction. Other objects and features will be in part apparent and in part pointed out hereinafter.